The occurrence of dramatic changes in mood, behavior, cognition and somatic functioning in some women in relation to the menstrual cycle has recently been the focus of a great deal of public scrutiny. This project is designed to study the psychobiology and treatment response of women with well defined menstrually-related mood disorders. The longitudinal screening methods developed by this group are capable of distinguishing women with menstrually-related mood syndromes from those who only believe that they have such a syndrome. With these methods, we have identified the following: 1) the absence of different amounts or patterns of secretion of gonadal steroids or gonadotropins in well-defined patients with menstrually-related mood disorder and controls; 2) an excess prevalence of history of formal psychiatric disorder in patients who failed to demonstrate, but nonetheless complain of, menstrually-related mood disorder, compared with patients with confirmed menstrually-related mood disorders; 3) the inability of answers to historical questions about the pattern and severity of menstrually-related mood changes to predict the existence of these changes; 4) the absence of state-related disturbances of response to dexamethasone in patients with menstrually-related mood disorder; and 5) the absence of superior efficacy of progesterone relative to medroxy-progesterone or placebo in the treatment of menstrually-related mood disorders. The goals of this project are to detect and accurately describe menstrually-related mood disorders, explore their pathophysiology and response to pharmacological and environmental manipulation, and to document the relationship between reproductive endocrine change and disorders of mood as a way of further investigating the neurobiology of psychiatric illness.